Deep under the hot, dusty streets of Balabad, a stash of priceless ancient treasure has lain hidden for centuries, protected by seven secret keys scattered around the globe. Secret, until now. When Oliver Finch and his friend, Zee, stumble across one of the precious objects, they are catapulted into the murky underworld of the city, where thieves lurk and people vanish without trace - and come face-to-face with a criminal mastermind who will stop at nothing to get hold of that key.